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Stachys brachyclada de Noé ex Coss. (Lamiaceae) is a quite rare medicinal plant endemic to the Mediterranean basin. In this study, seven secondary metabolites from a methanol extract of its leaves have been isolated and identified by a combination of chromatographic and spectroscopic methods (1D and 2D NMR experiments and ESIMS analysis). They include one ethyl 4-hydroxybenzoate (1), three acylated flavone glycosides (2-4), one diapigenin derivative (5) and two flavone aglycones (6-7). Stachysetin (5) was found the major compound of the extract (74.0 mg/g of dry matter). Moreover, the produced extract showed the ability in inhibiting the α-glucosidase enzyme (IC50 = 13.7 µg/mL), in quenching the radical 1,1-diphenyl-2-picrylhydrazyl (EC50 = 74.6 µg/mL), and in reducing the intracellular oxidative stress level in Human Dermal Fibroblast (64% inhibition at 50 µg/mL). [ABSTRACT FROM AUTHOR]

A new phloroglucinol derivative, identified as 3-benzoyl-3-hydroxy-5-(3-methylbut-2-en-1- yl)cyclopentane-1,2,4-trione (1), together with eight previously reported compounds, quercetin, myricitrin, hypericin, biapeginin, pseudohypericin, myricetin, 1,3,5,6-tetrahydroxyxanthone, and β-sitosterol were isolated from the chloroform, ethyl acetate and butanol extracts of the aerial part of Hypericum afrum (Lam.). Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR and HRESIMS. The EtOAc extract showed moderate MAO-A inhibition with an IC50 value of 3.35 μg/mL. Bioassay-guided fractionation of the EtOAc extract resulted in the isolation of quercetin as the active component exhibiting MAO-A inhibitory activity with an IC50 value of 1.25 μM. [ABSTRACT FROM AUTHOR]